Quad Ngon Modeling Techniques
vertex
Hi there,
I wanted your guys advise on how I should be going about modeling hardsurface objects. I am quite stuck in a pure quad mentality which I realize is silly and I am starting to see the pro's to utlizing n gons.
I did a quick model of a power socket piece to test two different methods of modeling. The first images are of the pure quad model. The second contains n gons.
I have a few questions about the two methods.
1. For the pure quad method things can get quite insane if you build a object that has say 20 different holes and indents in them and try to build supporting edges for each. I find Loop cuts don't work as you will just have to many and your mesh will become crazy and unmanageable. In my quad example my custom cut method worked well however if the top and bottom of that shape were rounded it would really distort the overall look. It's why I couldn't do loop cuts to support those square holes as it would of distorted the side round shape. So in a nutshell I am just banging my head against a wall when it comes to doing things with pure quads and even more so with more complex objects. I can't imagine doing something like millennial falcon with pure quads. Any advise would be much appreciated.
2. For the ngon version I did a bevel on the edges which worked nicely. My concern about this method is when I go to texture won't it cause issues? For example if I want to do some custom texture on areas where there are n gons won't there be stretching? If I want to unwrap the object and texture a small sticker on an area with ngons would that cause issues? Any advise on when to use this method would be appreciated.
Thanks so much guys!
Quads
Ngons
I wanted your guys advise on how I should be going about modeling hardsurface objects. I am quite stuck in a pure quad mentality which I realize is silly and I am starting to see the pro's to utlizing n gons.
I did a quick model of a power socket piece to test two different methods of modeling. The first images are of the pure quad model. The second contains n gons.
I have a few questions about the two methods.
1. For the pure quad method things can get quite insane if you build a object that has say 20 different holes and indents in them and try to build supporting edges for each. I find Loop cuts don't work as you will just have to many and your mesh will become crazy and unmanageable. In my quad example my custom cut method worked well however if the top and bottom of that shape were rounded it would really distort the overall look. It's why I couldn't do loop cuts to support those square holes as it would of distorted the side round shape. So in a nutshell I am just banging my head against a wall when it comes to doing things with pure quads and even more so with more complex objects. I can't imagine doing something like millennial falcon with pure quads. Any advise would be much appreciated.
2. For the ngon version I did a bevel on the edges which worked nicely. My concern about this method is when I go to texture won't it cause issues? For example if I want to do some custom texture on areas where there are n gons won't there be stretching? If I want to unwrap the object and texture a small sticker on an area with ngons would that cause issues? Any advise on when to use this method would be appreciated.
Thanks so much guys!
Quads
Ngons
Replies
So if it bakes OK without too many artifacts, then it's done, move onto the next piece. It doesn't matter if it's a polygon soup. It's just a means to an end.
Generally though for the in-game model it's better to have a nice edge-loop topology, for easier UV seams, and easier rigging for animation.
YMMV though, don't trust what anyone says. Test it out yourself to get the most bang for your buck. http://polycount.com/discussion/171153/the-death-of-curiosity
http://wiki.polycount.com/wiki/Subdivision_Surface_Modeling
Thanks again @Eric Chadwick
I just encountered a separate issue when trying to do texturing on a higher res mesh. My process is to export to obj and unwrap the object in z brush using custom polygroup selections. My mesh looks fine but when it unwraps my polys get warped. I have researched this online but just figure out why this happening. Low poly mesh this method worked fine. Any ideas?? @Eric Chadwick
In other words : Whenever using an automated UV solution, be prepared to have to project texture information. But if you want to texture the asset in such a way that a straight element of the texture also appears straight on the model, then there is no way around it, you'll have to put the effort into learning proper (as in, 100% controlled) UV techniques.
My process is to export to obj and unwrap the object in z brush using custom polygroup selections
That's a great approach for prototyping and quick tests, but that will never be satisfactory for clean, tight assets. Case in point with your unwrap here, which shows about 75% of wasted space and not a single piece laid straight
Of course there are hybrid approaches too (like only unwrapping a given part of a model if the rest doesn't require UVs ; being creative with UV island scale to maximize detail, and so on) but all these require solid UV skills to begin with. Good luck !
And yeah, same with the UV's. Dont auto them - and if you do, clean 'em up
For High Poly modeling, it is usually best to keep quads where you can to make life easier on yourself, but n-gons and tri's are sometimes a must to get proper shading for the bake. I use n-gons quite frequently, sometimes an n-gon will actually shade better than a a quad or tri as reduces the chance of pinching on flat or low detail surfaces. Claiming tri's and n-gons are flat out not okay is a mistake, as whatever gets you quality the fastest and most efficiently, the better. Check out the "How to model dem shapes" thread, it is filled to the brim with examples of n-gons and tri's being used properly.
Pior nailed it in terms of UV'ing advice.
I'm so confused about this ngon tri thing. I've never seen someone model this way before, full of ngons and tri's. Is all that matters when it comes down to it is that smooths properly? It looks like he just confirms visually that it looks good and doesn't worry about it too much. Or am I misinterpreting what he's doing ( can't hear what he's saying).
@musashidan hit the nail on the head with his break down of the LP mesh.
As for the video, he is modeling the highpoly mesh and is using n-gons, similar to what I had stated in my previous post. It is 100% okay to use n-gons when generating your initial high poly mesh, as most times you will apply some sort of smooth/remesh process before exporting and/or triangulate your mesh for complete control of your results when baking. If you rely solely on, lets say xnormal, to triangluate your mesh when importing, you can run into areas where you might have long quad faces and when it triangulates both your HP and LP mesh the edge it adds might be in different places and result noticeable shading differences between meshes. This sometimes can result in some funky bake artifacts.
Like I said before, when modeling my HP in Maya I do not have to worry too much about my HP topology in regards to n-gons, tri's, and quads. I simply generate the best smoothing mesh I can, in usually the most time efficient manner, and then use Convert > Smooth Mesh Preview to Polygons to then turn my smooth mesh preview of my initial HP mesh + a triangulation, usually into the final export mesh I will use for baking through XNormal or Substance. When using the conversion, it usually retopo's the entire mesh into Quads and Tri's and gives me a really solid output mesh to bake with. This results in no errors or warnings in zbrush or xnormal, and is super efficient time-wise.
This is my personal workflow, and many others have their own preferences. Just like any other art form, there is very rarely any set rules about how you create your models
As to your question I would terminate the loops. Once you have even sets of edgeloops that you want to terminate, you can always maintain quads.